Components for modular stairway system

ABSTRACT

The present staircase (S′, S″) includes a permanent framing ( 200, 300 ) made of metallic stringers ( 208 ), one of which being typically secured to a half-timbering (F). Vertically extending step supports ( 210 ) are secured along the stringers ( 208 ) and each include upper and front flanges ( 254 ) adapted to be secured respectively to a tread ( 204, 304 ) and to a riser ( 206, 306 ) of each step ( 202, 302 ) of the staircase (S′, S″). Various support systems, including a corner post ( 312 ) and brackets ( 328, 332, 338 ) mounted thereto, are provided for supporting various horizontal ( 226   c ) and angled ( 208   b,    208   d ) structural components of the framework ( 300 ) of the staircase (S″) when the staircase (S″) is L-shaped or U-shaped thereby including a turn in the staircase with flaring steps ( 103, 104, 105 ), and also possibly a landing ( 110 ). If the staircase (S′, S″) has an exposed side, various decorative or finishing wooden components, including treads ( 304 ), risers ( 306 ), false or decorative stringers ( 346, 350, 352, 360 ), mouldings ( 344, 348, 362 ), etc., are provided to completely cover the structural metallic framework ( 300 ), including the stringers ( 208   b,    208   d ). On the outside, or large, ends of corner steps ( 103, 104, 105 ), metallic L-shaped stringers ( 326 ) may be mounted to the dwelling&#39;s framework (F) and used to support the steps ( 302 ) instead of the aforementioned step supports ( 210 ).

RELATED APPLICATIONS

[0001] This is a continuation of International PCT Application No.PCT/CA01/00254 filed on Feb. 26, 2001, which claims benefit of CanadianApplication No. 2,299,604 filed Feb. 25, 2000.

BACKGROUND OF THE INVENTION

[0002] 1. Field of the Invention

[0003] The present invention relates to staircases and, moreparticularly, to components for staircases made of pre-measuredcomponents for partial or complete assembly thereof in the plant or madein the form of a kit for assembly on site.

[0004] 2. Description of the Prior Art

[0005] Typically, staircases are completely produced on site with thevarious wood components being cut to size as the staircase isprogressively erected on site. Furthermore, the finishing of a staircaseis often damaged during construction, namely the carpeting which coversthe steps or the solid wood finishing thereof. It is virtuallyimpossible to defer the installation of the finishing covering of thesteps of the staircase until the end of the construction therebyresulting in damages to this finishing during the final stages of theconstruction.

[0006] Also, it has been proposed to completely assemble a staircase inthe factory such that a pre-assembled staircase is delivered to theconstruction site for direct and easy installation thereat. Such amodular staircase is disclosed in the present inventor's co-pendingCanadian Application No. 2,149,981 which was laid-open for publicinspection on Nov. 24, 1995. In such a case, a modular staircase withoutits finishing covering is delivered on site and installed thereat. Oncethe finishing covering, e.g. carpeting, solid wood, etc. has beeninstalled on the staircase, it might again be subject to damage beforethe construction process is completely finished.

SUMMARY OF THE INVENTION

[0007] It is therefore an aim of the present invention to provide anovel staircase made of individual components manufactured to size inplant which, in the form of a kit, can be assembled together andinstalled on site or which can be mostly assembled together in plant andthen installed on site.

[0008] It is also an aim of the present invention to provide a staircasemade of individual components manufactured to size such that they canthen be assembled together and installed on site, or alternativelymostly assembled together in plant and then installed on site, includinga staircase frame and a finished wood covering therefor.

[0009] It is a further aim of the present invention to providecomponents for staircase systems adapted to be assembled on site, oralternatively mostly assembled together in plant and then installed onsite, such components including staircase frame elements and a finishedwood covering therefor.

[0010] Therefore, in accordance with the present invention, there isprovided a modular framework for a staircase, comprising at least twonon-wooden stringers and a series of non-wooden step supports adapted tobe mounted to the stringers for supporting a number of steps when thestringers are installed in a dwelling, wherein said step supports areadjustably installed to said stringers at predetermined locationstherealong such that the steps can be directly mounted to said stepsupports and into proper position thereof for the staircase, wherein anupper end of at least one of said stringers is supported by at least onevertical support located on one side of the framework, said verticalsupport being retained in position at least by at least one horizontalsupport, said horizontal support being secured at opposed end sectionsthereof to said vertical support and to outside elements of saidframework located on an other side of the framework located oppositesaid one side and anchored to the dwelling, wherein said verticalsupport comprises, on said one side, at least one post and at least onebracket secured thereto and, on said other side, at least one of saidoutside elements of said framework, whereby a riser and a tread of astep can be secured to said vertical support.

[0011] Also in accordance with the present invention, there is provideda vertical support for a modular framework for a staircase, theframework being of the type comprising at least two non-wooden stringersand a series of non-wooden step supports adapted to be mounted to thestringers for supporting a number of steps when the stringers areinstalled in a dwelling, said vertical support comprising, on one sideof the framework, at least one post and at least one bracket securedthereto, said vertical support being adapted to be retained in positionat least by one horizontal support that is secured at opposed endsthereof to said vertical support and to outside elements of theframework located on an other side of the framework located oppositesaid one side and anchored to the dwelling, wherein an upper end of atleast one of the stringers is supported by said vertical support,whereby a riser and a tread of a step can be secured on said one side tosaid vertical support, and on said other side to the outside elements.

[0012] Further in accordance with the present invention, there isprovided a modular framework for a staircase, comprising at least twohidden structural stringers and a series of step supports adapted to bemounted to the hidden stringers for supporting a number of steps whenthe hidden stringers are installed in a dwelling, wherein said stepsupports are installed to said hidden stringers at predeterminedlocations therealong such that the steps can be directly mounted to saidstep supports and into proper position thereof for the staircase, anumber of steps, each including a tread and a riser, being mounted tosaid framework, at least one decorative stringer being provided formounting to said framework, including to at least one of said hiddenstringers, for concealing said hidden stringers and said step supports.

BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Having thus generally described the nature of the invention,reference will now be made to the accompanying drawings, showing by wayof illustration a preferred embodiment thereof, and in which:

[0014]FIG. 1 is a schematic side elevational view of a staircase inaccordance with the present invention shown in a first state thereof;

[0015]FIG. 2 is a schematic side elevational view similar to FIG. 1 butshowing the staircase in a second state thereof;

[0016]FIG. 3 is a schematic front elevational view, partly broken away,of the staircase of FIG. 2;

[0017]FIG. 4 is a detailed view of the sliding anchor for adjustablestep support of FIG. 2;

[0018]FIG. 5 is a schematic side elevational view similar to FIG. 2 andshowing details of the assembly of the risers and the steps to the stepsupport attached to the stringers;

[0019]FIG. 5A is a cross-sectional view taken along section line A ofFIG. 5;

[0020]FIG. 5B is a cross-sectional view taken along section line B ofFIG. 5;

[0021]FIG. 6 is a schematic top plan view of a staircase in accordancewith the present invention;

[0022]FIG. 7 is a schematic top plan view of a support for an angularsection of the staircase;

[0023]FIG. 7A is a schematic elevational view of the support of FIG. 7;

[0024]FIG. 8 is a top plan view of the angular section of the staircaseand schematically showing the support of FIG. 7 and various bracketsused in the support frame of the angular section of the staircase;

[0025]FIGS. 8A to 8E are schematic views of various support structuresused in the framing of the angular section of the staircase of FIG. 8;

[0026]FIGS. 9A to 9E show various brackets used in FIG. 8;

[0027]FIG. 10 is a perspective view of a framework of a secondembodiment of a staircase also in accordance with the present invention,the framework being shown mounted to a dwelling's wall framework;

[0028]FIG. 11 is a perspective view similar to FIG. 10 but showing someof the staircase's steps mounted to the framework;

[0029]FIG. 12 is a perspective view similar to FIG. 11 but showing moreof the staircase's steps mounted to the framework;

[0030]FIG. 13 is a front elevational view of the framework of FIG. 10which also shows additional upper components of the framework;

[0031]FIG. 14 is a top plan view of the framework of FIG. 13;

[0032]FIG. 15 is a bottom perspective detailed view of part of theframework and of the steps of FIG. 12;

[0033]FIG. 16 is a bottom perspective detailed view of another part ofthe framework and of the steps of FIG. 12;

[0034]FIG. 17 is an elevational detailed view of a part of the frameworkand showing the assembly of sub-components thereof;

[0035]FIG. 18 is a detailed view of part of the framework and showingthe assembly of sub-components' thereof;

[0036]FIG. 19 is a cross sectional view taken along line 19-19 of FIG.18;

[0037]FIG. 20 is a detailed view of part of the framework and showingthe assembly of sub-components thereof;

[0038]FIG. 21 is a cross sectional view taken along line 21-21 of FIG.20;

[0039]FIG. 22 is a detailed view of part of the framework and showingthe assembly of sub-components thereof;

[0040]FIG. 23 is a cross sectional view taken along line 23-23 of FIG.22;

[0041]FIG. 24 is a schematic perspective view of a framework of a thirdembodiment of a staircase also in accordance with the present invention,the framework being shown mounted alone, that is without the dwelling'swall framework to which the staircase framework is mounted, and withFIG. 24 also showing a pair of wooden treads mounted to corner steps ofthe staircase framework;

[0042]FIGS. 24A and 24B are enlarged detailed views of FIG. 24;

[0043]FIG. 25 is an enlarged schematic perspective view, similar to FIG.24, but partly shown in exploded manner, and also showing the dwelling'swall framework, while not showing the treads of FIG. 24;

[0044] FIGS. 26 to 30 are views of various wooden components which canbe used with the staircase framework of FIG. 24, wherein FIGS. 26A and26B are respectively side elevational and perspective views of a firstmoulding, FIGS. 27A and 27B are respectively side elevational andperspective views of a first “false” stringer, FIGS. 28A and 28B arerespectively side elevational and perspective views of a secondmoulding, FIGS. 29A and 29B are respectively side elevational andperspective views of a second “false” stringer, and FIG. 30A is a sideelevational view of a third “false” stringer;

[0045]FIG. 31 is a schematic perspective view of various finishingwooden components mounted to the staircase framework;

[0046]FIG. 32 is an enlarged schematic front elevational view of part ofthe staircase framework and finishing wooden components mounted thereto;

[0047] FIGS. 33 to 36 are various perspective views showing variousfinishes around the staircase framework; and

[0048] FIGS. 37 to 42 respectively show side elevational, top plan andfour perspective views of various stages of assembly of the staircaseframework of the present invention, wherein FIGS. 39A and 39B areenlarged exploded detailed perspective views of FIG. 39, FIGS. 40A and40B are enlarged detailed perspective views of FIG. 40, FIGS. 41A and41B are enlarged detailed perspective views of FIG. 41, FIGS. 41C and41D are enlarged exploded detailed perspective views of FIG. 41, FIGS.42A, 42D and 42E are enlarged detailed perspective views of FIG. 42,FIGS. 42B and 42F are enlarged exploded detailed perspective views ofFIG. 42, and FIG. 42C is an enlarged detailed top plan view of FIG. 42.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0049] FIGS. 1 to 23 are described in PCT Publication No. WO 00/01902published on Jan. 13, 2000 based on PCT Application No. PCT/CA99/00607filed on Jun. 30, 1999.

[0050]FIG. 6 shows a top plan view of a staircase S in accordance withthe present invention, wherein, from the ground up, there are threestraight steps 100, 101 and 102, followed by an angular section of thestaircase S including flaring steps 103, 104 and 105. Then, thestaircase S includes four straight steps 106, 107, 108 and 109, followedby a landing 110, and then by three straight steps 111, 112 and 113.

[0051] Now referring to FIG. 2, a steel C-shaped stringer 10 is used oneach side of the staircase S, the stringers 10 being attached withscrews 11 to structural wooden components, such as half-timberings, inthe form of a wall stud 12 in FIG. 3. The angle of the stringers 10 isgoverned by the height of the risers of the staircase S.

[0052] The staircase S also includes successive steps 14 (also calledtreads) and risers 16. To attach the steps 14 and the risers 16 to thestringers 10, there are provided for each riser 16 and step 14 locatedthereabove an adjustable step support 18 in the form of a metallic platedefining planar upper and front perpendicular flanges 20 and 22 adaptedto respectively abut the step 14 and the riser 16 and to be attachedthereto, as seen in FIGS. 2 and 5. Angled oblong openings 24 are definedin one of the stringers 10 and the step support 18 to allow for therelative positioning of the step support 18 with respect to the stringer10 such that a same step support 18 can be used with risers 16 ofdifferent heights and steps 14 of different depth. More particularly, aslidable anchor 26 (see FIGS. 2 and 4) allows for the step support 18 tobe adjusted with respect to the stringers 10.

[0053] As seen in FIG. 3, a finished stringer covering 28 is provided onthe staircase S to provide an aesthetic finishing to the exposed side ofthe staircase S, that is the side thereof which is visible and thusopposed to the side anchored to the wall stud 12, in the case ofstaircases having one such exposed side.

[0054] In FIG. 2, the staircase S is shown in its finished state, thatis with aesthetic and quality steps and risers 14 and 16. However, thepresent modular staircase S has further use in that the finished stepsand risers 14 and 16 can be only installed to the step support 18 afterthe construction has been completed. During construction, the steps andrisers 14 and 16 are replaced by temporary steel steps and risers whichtake the form, as seen in FIG. 1, of a series of successive L-shapedunits 30, each including a horizontal section 32 which acts as a stepand a vertical section 34 which acts as a riser, the front edge of thehorizontal section 32 defining an inturned lip 36. These L-shaped units30 are temporarily secured to the steps support 18 such that thestaircase s can be used during construction without causing damagethereto. After the construction has been terminated, the L-shaped units30 are replaced by finished steps 14 and risers 16 (see FIG. 2).Therefore, the staircase S takes the form of a kit which, in itssimplest form, includes the stringers 10, the adjustable step support18, the temporary L-shaped step units 30 and the finished steps 14 andrisers 16.

[0055] As seen in FIG. 5, the upper and front flanges 20 and 22 of thestep support 18 are secured respectively to the steps 14 and risers 16by a series of screw 34 which extend through the flanges 20 and 22 andinto the steps 14 and risers 16 front the blind sides thereof. SectionsA and B of FIGS. 5A and 5B show these screws 38 extending through theflanges 20 and 22 of the step support 18. Adhesive 40 may be used tosecure the upper end of the riser 16 to the lower front end of the step14. Also, the lower end of the riser 16 may be secured to the rear endof the step 14 by way of an appropriate resin 42, such as apolyester-based resin which, once hardened, “welds” the woodencomponents together as described in details in aforementioned CanadianApplication No. 2,149,981.

[0056] The present invention also provides for various structuralcomponents for providing support to the staircase S. For instance, asupport post 44, shown in FIG. 7A, is used to support the convergingends of steps 103, 104 and 105 of the angular section of the staircase S(see FIG. 6). The vertical post 44 includes three support platesextending at different angles therefrom, namely a lower support plate46, an intermediate support plate 48 and an upper plate support plate 50adapted to be attached to different risers for respectively supportingsteps 103, 104 and 105. The lower end of the corner post 44 includes aconnecting plate 52 for attachment to a lower stringer 10, as seen inFIGS. 1 and 7A. With reference to FIG. 6, the support plates 46, 48 and50 of the corner post 44 are generally located at 54.

[0057]FIG. 8 is a top plan view of the angular section of the staircaseS including steps 103, 104 and 105. FIGS. 8A to 8D show various supportsand brackets for adjustably connecting the steps 14 and the risers 16 tothe stringers 10, including brackets 56, 58, 60, 62 and 64. The brackets56 to 64 are shown enlarged in FIGS. 9A to 9E, respectively. Thebrackets 56 to 64 are each made by bending black sixteen-gage steel.

[0058]FIG. 8E shows a connection between the stringer and the landing110.

[0059] Therefore, the present kit for erecting a staircase S can be usedfor a straight staircase as well as for a U-shaped staircase havingangular steps and landings. For the exposed side of the staircase, thestringers are attached one to another with rigid connecting systems andare bolted such as to obtain a complete stringer of crankshaft-shapewhich is self-supporting, the steps and the risers being pre-assembledin a single monocoque unit.

[0060] When necessary, such as the free bearing of straight stepsexceeds five of six step units, the stringer can be doubled (one uponthe other) to reinforce it and to minimise vibrations.

[0061] This framing is the only permanent part of the present kit as thesteps and risers can be replaced depending on the use of the staircase.

[0062] The L-shaped steel units 30 are made from folded steel and arebolted to the adjustable step support 18 to provide a temporarystaircase for use during construction, and in the case of a fireproofbuilding, the framing (e.g. the stringers 10) are screwed directly inthe concrete walls or other non-flammable facing, and appropriate steelrisers and steps (such as the L-shaped units 30) can then be used toobtain a fireproof staircase.

[0063] Once at the finishing step of the building, including any cabinetmaking step, the temporary or provisional steps, i.e. the L-shaped steelunits 30, are easily detached from the step supports 18 and replaced byprefabricated units made of solid wood or any other prefabricatedelements, these prefabricated units comprising steps 14 and risers 16,preferably made in a single monocoque assembly, and a finishing stringer28 made of solid wood which nests under the steps 14 and behind therisers 16 in addition to being attached with screws to the metalstringer 10 from inside.

[0064] The step supports 18 are made from light steel folded to formflanges 20 and 22 and are each connected to the stringers 10 by two keys26 capable of sliding in the C-shaped stringers 10 for allowing toshorten or lengthen the span of the steps 14 which varies in view of theheight of the risers 16. An additional adjustment is provided by way ofthe oblong openings 24 which allow for an adjustment of the height ofriser 16.

[0065] The present stairway system is thus universal in that it allowsfor the staircase to turn left or right, or remain straight. The cornerpost 44 for the angular section of the staircase being of differentconfiguration whether the staircase turns right or left.

[0066] FIGS. 10 to 23 illustrate a variant staircase S′ also inaccordance with the present invention. The staircase S′ comprisesbasically a framework 200 and a series of steps 202. The steps 202 canbe temporarily mounted to the framework 200 during the constructionperiod and then can take the form of permanent steps. The steps 202 areherein L-shaped and each step 202 includes a horizontal section or tread204 and a vertical section or riser 206.

[0067] The framework 200 includes a series of components, some of whichbeing cut to size in the plant such that all of the components of theframework 200 can be assembled together and installed on site withminimal adjustment, if any. Alternatively, at least part of thesecomponents can be assembled together in the plant, perhaps in modularsections, and then installed on site.

[0068] More particularly, the framework 200 comprises elongatedstringers 208, each typically made of a metallic material or any othersuitable material, e.g. composite plastic, capable of sustaining theloads to which it is subjected (including the steps 202 and standardloads to be supported by any staircase), and adjustable step supports210 mounted inwardly of the stringer 208. The stringers 208 have theconfiguration of C-shaped channels (see, for instance, FIGS. 16 and 19).The step supports 210 are also each typically made of a metallicmaterial or any other suitable material, e.g. composite plastic, capableof sustaining the loads to which it is subjected (including the steps202 and standard loads to be supported by any staircase).

[0069]FIG. 10 shows a stringer 208 a (i.e. a closed stringer) and fourstep supports 210 fixedly mounted thereto on one side thereof with theother side of the stringer 208 a being secured to a wooden framework Fof the dwelling where the staircase S′ is being installed. Facing thestringer 208 a, there is a stringer 208 b (i.e. an open stringer) whichextends at a location in the dwelling where there is no framework F,whereby the stringer 208 b must itself be fixedly supported by othermeans than the framework F. For this purpose, there is provided avertical post 212 and the stringer 208 b is secured to a lower end ofthe post 212 by a link 214. More particularly, the link 214 defines asleeve 216 at its upper end which is engaged around the post 212 andfixed thereto typically by welding, although these components could bebolted or otherwise attached together. As seen in FIGS. 18 and 19, thelink 214 is imprisoned at its lower end between a plate 218 and a web220 of the stringer 208 b by way of bolts 222 and nuts 224, the boltsextending through holes defined in the plate 218 and in the web 220 ofthe stringer 208. A foot member 215, similar to link 214 but with asupport plate at is free end instead of sleeve 216, is mounted to thelower end of stringer 208 b in a way similar to link 214.

[0070] Now returning to FIG. 10, above the stringers 208 a and 208 bwhich are to support four steps 202, the next steps negotiate a 90° turn(see FIG. 14) consisting of three triangular steps which are supportedby elongated horizontal supports 226 (i.e. supports 226 a, 226 b, 226 cand 226 d) which resemble the stringers 208. The outside ends of thesehorizontal supports 226 are secured in position to the framework F withsimilarly configured plates 230 (best seen in FIGS. 20 and 21) and theirinside ends are secured to the post 212 using a series of similarlyconfigured links 228 (best seen in FIGS. 22 and 23).

[0071] More particularly, each link 228 includes at one end a sleeve 232surrounding the post 212 and welded thereto, and at an opposite end aflat section 234 defining holes though which extend bolts 236 with theflat section 234 being retained to the horizontal support 226 by itbeing urged towards the inside of lips 238 of the horizontal support 226by the bolts 236 which coact with nuts 240 and washers 242 which bearagainst the outside of the lips 238. It is noted that both thehorizontal supports 226 c and 226 d are mounted to the post 212 with asingle link 228 which has one sleeve 232 and two flat sections 234, i.e.one for connection to each horizontal support 226 c, 226 d.

[0072] Each plate 230 has an inner end 243 secured to the inside of thehorizontal support 226 (see FIGS. 20 and 21) by way of bolts 244 andnuts 246, and an outer end 248 angled with respect to the inner end 243such as to bear against the framework F and held thereto with screws, orthe like, driven through holes defined in the outer end 248.

[0073] As best seen in FIGS. 13 and 14, the two next steps are supportedby stringers 208 c and 208 d and two step supports 210 are mounted toeach of these stringers. Stringer 208 c is mounted to the framework F,whereas stringer 208 d is supported at its lower end by the post 212(using a further link 228) and its upper end by a further post 250 whichis similar in configuration and identical in function to the post 212.

[0074] A pair of further horizontal supports 226 (i.e. supports 226 eand 226 f) are mounted, as the earlier supports, at their outside endsto the framework F (using plates 230) and at their inside ends to post250. The two supports 226 e and 226 f are at a same level such that thestaircase S′ defines therebetween a landing area.

[0075] Then, two stringers 208 e and 208 f extend parallelly upwardlyfrom the horizontal support 226 f and four step supports 210 are mountedto each of these two stringers 208 e and 208 f for providing fourstraight steps above the landing area which are similar to the stepssupported by the bottom stringers 208 a and 208 b.

[0076] It is noted that, even though the present posts 212 and 250 havebeen herein illustrated with circular cross-sections, these posts mayalso be of different tubular shapes, e.g. of square cross-section. Also,the sleeves 216 and 232 respectively of links 214 and 228 can, asidefrom being welded to the posts 212 and 250, be secured alternatively beattached thereto on site by way, for instance, of set screws extendingradially through the sleeves 216/232 and into the wall of the posts 212and 250 thereby allowing for on site positioning and/or adjustment ofthe links 214/228 to the posts 212/250. In such a case, the posts212/250 would define a series of threaded holes disposed verticallytherealong for allowing the links 214/228 to be adjusted height-wise onsite relative to the posts 212/250.

[0077] Therefore, the framework 200 generally consists, for straightruns, of stringers 208 provided with step supports 210; for angled runs,of horizontal supports 226 a to 226 d; and, for landing areas, of a pairof horizontal supports 226 e and 226 f. The stringers 208 and horizontalsupports 226 are mounted at their closed end to the dwelling's frameworkF and at their open end to the posts 212 and 250 and the latter aremaintained in position by their rigid connections to the horizontalsupports 226 and to the stringers 208 which are themselves firmly andsafely anchored to the framework F. The free ends of the stringers (i.e.lower ends of stringers 208 a and 208 b and upper ends of stringers 208e and 208 f) may be secured to the dwelling's floor structure.

[0078] As seen in FIGS. 15 to 17, the step supports 210 each have arectangular shaped body 252 with perpendicular flanges 254 extendingperipherally therefrom. The steps supports 210 may be welded to thestringers 208 or may secured thereto with a plate 256 (see FIG. 17)located inside the stringer 208 and bolt and nut arrangements 258extending through the plate 256 and through the body 252, the lips 238of the stringer 208 being sandwiched between the plate 256 and the body252 such that the step support 210 is held firmly against the stringer208. The step support 210 defines oblong holes 260 for allowingdifferent relative positions between the step support 210 and thestringer 208 thereby allowing for steps of different tread depths andriser heights. Also, the step support 210 has a generally symmetricconfiguration (e.g. at the level of its oblong holes 260) such that itcan be used on either left-hand or right-hand stringers, e.g. stringers208 b and 208 a, respectively.

[0079] The steps 202 can be attached in different ways to the stepsupports 210 and horizontal supports 226. For instance, in FIG. 15, theflange 254 of the step support 210 is secured to the riser 206 of thestep 202 by a wing nut 262 screwed to the riser 206 and engaging theflange 254 with one of its wings. Also, screws could be driven throughopenings 264 defined in the flanges 254 and into the back of the step202. Glue could also be used to secure the step 202 to the flanges 254.

[0080] The steps 202 can be similarly secured to the horizontal supports226 by using glue as in FIGS. 15 and 16 where webs 265 of the supports226 bear against the risers 206 of the steps 202. Screws can also bedriven through openings 266 defined in the webs 265 and into the steps202.

[0081] Conveniently, when temporary steps are installed in the staircaseS′, easily releasable means (such as wing nuts 262) are preferably usedto mount the steps 202 to the framework 200. The permanent steps canthen be mounted to the framework using these same releasable meansand/or other means (e.g. glue, screws, etc.).

[0082] The above components are preferably all manufactured to size inthe plant as opposed as on the site, and this can be done by having thedimensions of the staircase to be installed. The components can be allassembled on site as a kit, or can be assembled in one or more modularsections to finally assembled together on site. It is convenient tofixedly mount in plant the components which depend from the posts (212,250); similarly, it is preferable to fix the step supports 210 to thestringers 208 in the plant. If possible, the whole assembled framework200 is permanently produced in the plant such that only the connectionsthereto with the dwelling's framework F are effected on site.

[0083] The components of the framework 200 must be sufficiently rigidand strong to sustain the loads to which they are subjected, includingthe weight of some of the components of the framework 200 itself, theweight of the steps 202 and the weight that the staircase S′ must beable to support.

[0084] If both the stringers 108 a and 108 b are of the closed type,they will both be secured to the framework F as stringer 108 a of FIGS.10 to 12. Similarly, if both sides of the staircase S′ are closed, theposts 212 and 250 may not be required as framework F will be present tosupport the stringers 208 as well the both ends of each horizontalsupport 226.

[0085] The present system offers a great economy in wood as theframework 200 is generally all made of metallic material (with rigid andstrong plastics being also usable), and the use of such a metallicframework 200 provides generally more rigidity to the staircase S′. Thepresent connections between the framework 200 and the steps most likelyreduce squeaking in the staircase S′.

[0086]FIG. 24 illustrates a further variant staircase S″ also inaccordance with the present invention. The staircase S″ comprisesbasically a framework 300 and a series of steps 302 to be mounted to theframework 300. As for staircase S′ of FIG. 10, the framework 300 of thestaircase S″ of FIG. 24 includes stringers 208 a, 208 b, 208 c and 208 dand a series of step supports 210 mounted to these stringers. Theframework for the corner steps is different in FIG. 24 than that of FIG.10, although a similar pivot post 312 is used on the inside of thecorner steps to link the stinger 208 b to the stringer 208 d and toprovide supporting brackets or links 328 to support the inside ends ofthe corner steps. In FIG. 24, two such corner steps are shown at 302.Each corner step 302 includes at least a tread 304 and a riser (notshown in order not to hide the framework 300). In FIG. 10, variouselongated horizontal supports 226 are used to support the steps 202,whereas in FIG. 24, L-shaped stringers 326 a and 326 b are used on theoutside end of the corner steps to support these steps 302, includingtheir treads 304 and risers. There is also provided L-shaped stringer326 c for a not shown further step 302. An elongated member 330 joinsstringers 326 b and 326 c. In succession, stringers 326 a and 326 b,elongated member 330 and stringer 326 c connect bottom stringer 208 a totop stringer 208 c and therefore the two straight runs of steps to upperand lower opposed ends of the corner steps structure.

[0087] The top end of stringer 208 b is provided with a connecting plate332 having at its free end a square sleeve 334 to which the lower end ofthe pivot post 312 extends and is secured by way of bolts or screws 336.The upper end of the post 312 is mounted by way of connecting plate 338to the lower end of stringer 308 d. The elongated horizontal support 226c extends horizontally between the upper end of the pivot post 312 andthe horizontal section of L-shaped stringer 326 c.

[0088] As seen in FIG. 25, the L-shaped stringer 326 and/or theelongated member 330 are mounted to the framework F of the dwellingusing any suitable fastener, including that illustrated at 340.Additional connecting plates 342 are mounted to the horizontal sectionof L-shaped stringer 326 a and to the elongated member 330 such as toextend vertically such that the risers can be mounted at their outsideends to these connecting plates 42 and at their inside ends to theconnecting plates 328.

[0089] FIGS. 26 to 30 show various finishing wooden elements which canbe mounted to the staircase S″ and conceal the same. FIGS. 26A and 26Billustrate a first moulding 344; FIGS. 27A and 27B illustrate a first“false” stringer 346; FIGS. 28A and 28B illustrate a second moulding348; FIGS. 29A and 29B illustrate a second “false” stringers 350; andFIG. 30A illustrate a third “false” stringer 352. In FIG. 31, some ofthese wooden components are shown mounted to the staircase framework300. In addition to the stringer 208 b and the step supports 210, thereis shown a hidden elongated wooden structural member 354, mountedparallel and below to the stringer 308 b, as well as a gypsum panel 356.Two treads 304 and one riser 306 are shown mounted to the step supports210. The first moulding 344 is mounted to the gypsum panel 356, whereasthe first false stringer 346 is mounted to the stringer 308 b and/or tothe wooden structural member 354 with an appropriate one of the secondand third false stringers 350 and 352 being mounted opposite arespective step support 210 and above the first false stringer 346. Thesecond moulding 348 is mounted between the first false stringer 346 andthe second or third false stringer 350, 352 with the latter beingmounted against the riser 306 and under the tread 304.

[0090] In FIG. 32, the positioning of the second moulding 348 betweenthe first false stringer 346 and one of the second and third falsestringers 350 and 352 is better shown.

[0091] In FIG. 33, a gypsum panel 358 is shown mounted to the frameworkF of the dwelling. In FIG. 34, a “false” stringer 360 is shown mountedagainst the riser 306 and the tread 304 with FIG. 34 also showing amoulding 362 for the false stringer 360. In FIG. 35, various steps 302are shown mounted to the framework 300 and a false stringer 360 ismounted to each step. FIG. 36 is an enlarged view of FIG. 35 but furtherprovided with the aforementioned moulding 362.

[0092] FIGS. 37 to 42 illustrate various assembly stages of the presentstaircase. For instance, the stringers 208 a and 208 c which areC-shaped and on the outside of the staircase are securely mounted to thewooden framework F by way of screws, e.g. using number 10 screws of 1.5″disposed at each linear foot with two screws at each extremity of-thestringer. In some instances, additional wooden framework may have to beadded to the dwelling's framework F to receive the screws. At the top ofthe stringers 208 a and 208 b, there horizontally extends a reinforcingmember 364 (see FIGS. 24, 25, 41 and 42). Additionally, elongatedhorizontal support 226 c also acts as a reinforcing member between thelower ends of stringers 208 c and 208 d.

1. A modular framework for a staircase, comprising at least twonon-wooden stringers and a series of non-wooden step supports adapted tobe mounted to the stringers for supporting a number of steps when thestringers are installed in a dwelling, wherein said step supports areadjustably installed to said stringers at predetermined locationstherealong such that the steps can be directly mounted to said stepsupports and into proper position thereof for the staircase, at leastone vertical support comprising, on one side of the framework, at leastone post and at least one bracket secured thereto and, on an other sideof the framework located opposite said one side, outside elements ofsaid framework, said outside elements of said framework being anchoredto the dwelling, an upper end of at least one of said stringers beingsupported by part of said vertical support located on said one side ofthe framework, said vertical support on said one side being retained inposition by at least one horizontal support, said horizontal supportbeing secured at opposed end sections thereof to said bracket and to atleast one of said outside elements of said framework, whereby a riserand a tread of a step can be secured to said vertical support.
 2. Aframework as defined in claim 1, wherein said outside elements compriseat least one L-shaped stringer provided at said other side of saidframework, said post and said at least one L-shaped stringer beingadapted for supporting at least one corner step of the staircase.
 3. Aframework as defined in claim 2, wherein a number of said bracketsmounted to said post and a number of said L-shaped stringers mounted tothe dwelling are provided at various elevations for supporting a numberof corner steps of the staircase.
 4. A framework as defined in claim 3,wherein at least one of said brackets includes a tubular first endengaged around said post and secured thereto, and a plate-shaped secondend mounted to at least one of the tread of a step, the riser of a step,said horizontal support, and said stringer.
 5. A framework as defined inclaim 4, wherein said plate-shaped end defines openings such thatfasteners, including at least one of screws and bolts, can be extendedtherethrough for securing to said bracket said at least one of the treadof a step, the riser of a step, said horizontal support, and saidstringer.
 6. A framework as defined in claim 1, wherein at least oneconnecting plate extends from said outside elements for attachment tothe riser of the step.
 7. A framework as defined in claim 1, whereinsaid horizontal support comprises a metallic channel.
 8. A verticalsupport for a modular framework for a staircase, the framework being ofthe type comprising at least two non-wooden stringers and a series ofnon-wooden step supports adapted to be mounted to the stringers forsupporting a number of steps when the stringers are installed in adwelling, said vertical support comprising, on one side of theframework, at least one post and at least one bracket secured thereto,said vertical support being adapted to be retained in position at leastby one horizontal support that is secured at opposed ends thereof tosaid vertical support and to outside elements of the framework locatedon an other side of the framework located opposite said one side andanchored to the dwelling, wherein an upper end of at least one of thestringers is supported by said vertical support, whereby a riser and atread of a step can be secured on said one side to said verticalsupport, and on said other side to the outside elements.
 9. A modularframework for a staircase, comprising at least two hidden structuralstringers and a series of step supports adapted to be mounted to thehidden stringers for supporting a number of steps when the hiddenstringers are installed in a dwelling, wherein said step supports areinstalled to said hidden stringers at predetermined locations therealongsuch that the steps can be directly mounted to said step supports andinto proper position thereof for the staircase, a number of steps, eachincluding a tread and a riser, being mounted to said framework, at leastone decorative stringer being provided for mounting to said framework,including to at least one of said hidden stringers, for concealing saidhidden stringers and said step supports.
 10. A framework as defined inclaim 9, wherein said tread, said riser and said decorative stringer aremade of wooden material.
 11. A framework as defined in claim 9, furtherincluding at least one decorative molding for positioning adjacent tosaid decorative stringer.
 12. A framework as defined in claim 11,wherein decorative molding is made of wooden material.
 13. A frameworkas defined in claim 11, wherein said decorative stringer comprises afirst decorative stringer extending substantially opposite said hiddenstringer and a second decorative stringer extending substantiallyopposite at least one of one of said step supports, said decorativemolding extending between said first and second decorative stringers.